someone who acts/pretends like they are your friends or relatives but then when you turn your back and they see the opportunity they betray snitch or stab you in the back.

my aunts:one lives in the netherlands and one lives in the united states along with her husband my uncle in law are such doublecrossers they ratted on me when i went to study in the united states.they told the us customs i was going to study there.my aunt who lives in the netherlands was jealous because she didn`t get a trip to the united states and my uncle doublecrossed snithed me by telling he was going to have a party in his club and i was probably going to receive a girlfriend on a certain day/date.but that was false instead he lured me into a trap to deport me from the united states for his daughter`s personal gain.the teachers would allow her to the twelveth grade if he did so.